TWI870350B - Holding apparatus and method for holding a substrate - Google Patents

Abstract

The invention relates to a holding apparatus (100), in particular a chuck, for a substrate (101), comprising a main body (103) with a upper side (105), a carrier element (107), wherein the carrier element (107) is arranged in a recess (109) of the main body (103) so as to be vertically movable such that it can be adjusted between a protruding loading position and a retracted clamping position, and wherein the carrier element (107) comprises a support surface (111) for placement of the substrate (101), wherein the support surface (111) has a smaller diameter than the main body (103), and a lifting element which lifts the carrier element (107) to the loading position, wherein the carrier element (107) seals the recess (109) such that a sealed cavity (113) is provided between the main body (103) and the carrier element (107), which cavity (113) can have a negative pressure applied thereto which counteracts the effect of the lifting element.

Description

Holding device and method for holding substrate

The invention relates to the field of holding and fixing substrates, in particular in manufacturing equipment for microstructured devices.

Substrates such as semiconductor wafers are processed in special manufacturing plants for microstructure devices, for example in coating plants (coaters). In particular, substrate holders (so-called chucks) are often used in order to hold the substrates in these plants. Frequently, these are rotating chucks which rotate the substrate at a high rotation speed, for example in order to coat the substrate uniformly. The substrate is fixed to the chuck, for example, by vacuum suction.

Substrates processed in this way are mostly flat and planar. However, they can also deviate from the ideal planar shape and have a curvature. A curved wafer is defined as a warped wafer, for example. It is difficult to fix a curved substrate on a rotary chuck by vacuum suction, because due to the curvature no vacuum or only an insufficient vacuum can be established between the upper side of the chuck and the lower side of the substrate.

In order to improve the fixing of a bent substrate, it is known to provide a soft sealing lip on the supporting surface of a chuck. The substrate is supported on the periphery of the sealing lip, so that a vacuum can be established between the substrate and the chuck.

However, in this case, it is disadvantageous that the substrate is not guided horizontally during the suction process. While the air is being pumped away, the substrate can slide or float sideways in the holding surface and result in vertical movement until finally it is supported in a planar manner on the chuck. This adversely affects the centering of the substrate relative to the chuck, which can lead to undesirable effects in subsequent processes, such as vibrations or non-uniform (i.e. undulating) edge bead removal (EBR).

Further disadvantages are caused by contamination and aging of the sealing lips. The sealing lips can collect particles and their surface and friction properties change over time. This can lead to certain increased maintenance expenditures, for example due to replacing the sealing lips, correcting the storage position or cleaning the sealing lips.

Therefore, the object of the present invention is to efficiently and stably hold and fix a substrate, especially a curved substrate.

This objective is achieved by the characterization of the independent claims in the patent application. Advantageous developments are the subject matter of the dependent claims, the invention description and the drawings.

According to a first aspect, the invention relates to a holding device for substrates, in particular a chuck, comprising: a body having an upper side; a carrying element, wherein the carrying element is arranged in a recess of the body so as to be vertically movable so that it can be adjusted between a raised loading position and a retracted clamping position, and wherein the carrying element comprises a support surface for placing the substrate, wherein the support surface has a smaller diameter than the body; and a lifting element, which lifts the carrying element to the loading position; wherein the carrying element seals the recess so that a sealing cavity is provided between the body and the carrying element, which cavity can have a negative pressure applied thereto to counteract the effect of the lifting element. This offers the advantage that substrates to which suction cannot be easily applied (especially curved wafers) can be held securely and guided in the vertical movement due to the initially small vacuum surface.

The small size of the support surface of the carrier component means that in the loading position a sufficient seal can be achieved to initially fix the bent wafer on the carrier component. Subsequently, the substrate can be pulled against the upper side of the main body in the clamping position and finally clamped securely.

The upper side of the main body may correspond to the clamping surface for the substrate, on which the substrate is securely clamped in the clamping position.

In this context, vertical movement refers to movement coaxially with the transverse axis of the main body. In particular, this means movement perpendicular to the supporting surface of the carried element.

The diameter of the carrier element is, for example, smaller than half, one third or one quarter of the diameter of the substrate and/or the diameter of the body. In particular, in the case of significantly curved substrates, it is advantageous for the diameter of the carrier element to be as small as possible in order to generate sufficient vacuum suction in the loading position.

The carrier element may be configured so as to be movable in the recess in a piston-like manner.

The recess may be a depression in the body, in particular along a central axis of the body. The recess may have a circular diameter. The diameter of the recess may correspond to or may be minimally larger than the diameter of the carrier element.

The cavity may be the space maintained between the bottom of the depression and the carrier component. The size of the cavity may be defined by the position of the carrier component and may vary as the carrier component moves.

The substrate may be a wafer. The substrate may be dish-shaped. The substrate may have a mostly circular circumference and a diameter of 2, 3, 4, 5, 6, 8, 12 or 18 inches. Furthermore, the substrate may be mostly flat and may have a thickness between 50 and 4000 microns. The substrate may have straight edges (flat) and/or may have at least one notch. Furthermore, the substrate may have corners, in particular be square or rectangular.

The substrate may be formed of a semiconductor material (such as silicon [Si] or gallium arsenide [GaAs]), glass (such as quartz glass), a synthetic material, or a ceramic. The substrate may be formed of a single crystal, polycrystalline, or amorphous material. Furthermore, the substrate may include a variety of related materials.

The substrate may include circuits (such as transistors, light-emitting diodes or photodetectors), conductive tracks connecting these circuits, or optical devices and micro-electromechanical systems (MEMS) or micro-opto-electromechanical systems (MOEMS) structures. Furthermore, the substrate may have a coating, such as a structured chromium layer, a pre-crosslinked or hardened bonding adhesive or a separation layer.

According to one embodiment, a spacer is provided which defines a clamping position of the carrier element, where the support surface of the carrier element is arranged to be approximately flush with the upper side of the main body. This provides the advantage that the position of the carrier element can be fixed in the clamping position, so that the support surface and the upper side of the main body form a common support for the substrate, on which the substrate can be clamped in the clamping position.

Preferably, after lowering, the height deviation between the supporting surface of the carrier component and the upper side of the main body is smaller than the height fluctuation caused by deformation or bending of the substrate. Particularly preferably, the height deviation is smaller than the thickness of the substrate.

According to one embodiment, the body comprises sealing means, in particular a sealing lip, which surrounds the carrier element with a spaced interval and can seal between the upper side of the body and the substrate. This offers the advantage that the substrate can be sucked and clamped in a particularly efficient manner in the clamping position. With the aid of the sealing means, a vacuum can be generated under the substrate, which exerts a uniform force on the substrate and clamps it.

According to one embodiment, the carrier element is provided with a seal which bears against the side walls of the recess in the body. This offers the advantage of ensuring the tightness of the cavity and frictionless movement of the carrier element in the recess.

According to one embodiment, the carrier element comprises fixing means for fixing the substrate supported on the supporting surface (especially the suction opening). This provides the advantage that the substrate can be stably fixed on the supporting surface.

According to one embodiment, the main body has further fixing means to fix the lowered substrate on the upper side. The further fixing means may include further suction openings.

According to one embodiment, the cavity and the fixing means form a fluid connection. This has the advantage of allowing a particularly simple construction and control of the holding device. For example, a single pressure supply is sufficient to control the fixing of the substrate and the lowering of the carrier component.

According to one embodiment, the holding device has a pressure connector, by means of which the pressure in the cavity can be controlled. This offers the advantage of allowing the function of the carried component to be controlled by applying pressure, for example via an external pressure supply.

According to one embodiment, the lifting element comprises a clamping element, in particular a compression spring, which is designed to exert a force on the carrying element in order to raise it.

The lifting element generates a force on the carrying element, which counteracts the tension generated by the negative pressure in the cavity. The lifting element (especially the clamping element) can be arranged between the main body and the carrying element, especially in a recess of the main body.

Furthermore, the holding device can include a stopper, wherein the lifting element is designed to urge the carrying element against the stopper. The stopper defines, for example, the loading position of the carrying element and prevents the carrying element from sliding out of the recess.

According to one embodiment, the holding device comprises a rotating device for rotating the holding device, in particular the body and the carrier element. This provides the advantage that a substrate held particularly stably by the holding device can be rotated for further processing steps, such as applying a coating.

According to a second aspect, the present invention relates to a manufacturing apparatus for a microstructure device, comprising a holding device as described in any of the above-mentioned patent applications. This provides the advantage that substrates to which suction cannot be easily applied (especially curved wafers [bent wafers]) can be efficiently and stably held and handled in the manufacturing apparatus.

The manufacturing equipment can be a coater, a varnisher, a developer, a spin dryer, a mask aligner, a projection scanner, a laser stepper, a wafer bonder, a mask system, a cleaning system or an imprint system.

According to a third aspect, the present invention relates to a method for holding a substrate in a holding device, the holding device comprising a main body and a carrier element, wherein the method comprises the following method steps: raising the carrier element to a loading position, wherein the carrier element has a diameter smaller than the substrate; placing the substrate on a supporting surface of the carrier element; fixing the substrate on the supporting surface; and lowering the carrier element to a clamping position, wherein the supporting surface of the carrier element is configured to be approximately flush with the upper side of the main body. This provides the advantage that substrates to which suction cannot be easily applied (especially curved wafers [bent wafers]) can be stably held and guided in vertical movement due to the initially small vacuum surface.

The diameter of the carrier element is, for example, smaller than half, one third or one quarter of the diameter of the substrate and/or the diameter of the body. In particular, in the case of significantly curved substrates, it is advantageous for the diameter of the carrier element to be as small as possible in order to generate sufficient vacuum suction in the loading position.

The small diameter compared to the wafer size results in a vacuum surface that is initially smaller and easier to seal in order to apply suction to the wafer in the loading position. In particular, in the case of curved wafers, suction is simplified by the smaller vacuum surface. Subsequently, the substrate is pulled against the upper side of the main body, where it can finally be clamped securely over its entire surface in the clamping position.

According to a specific embodiment, in order to fix the substrate on the support surface, a first negative pressure is applied to the cavity of the holding device; and in order to lower the carrier component to the clamping position, a second negative pressure is applied to the cavity, wherein the second negative pressure is a pressure lower than the first negative pressure. This provides the advantage that the control of the holding device (especially the fixing of the substrate and the movement of the carrier component) can be implemented by a single pressure connector. Due to the change of the negative pressure, the substrate can be initially fixed, the carrier component can be adjusted, and then the substrate can be finally fixed.

According to one embodiment, placing the substrate onto the support surface of the carrier element generates a pressure drop in the cavity, in particular by sealing the suction openings on the support surface, wherein the lowering of the carrier element into the clamping position is triggered and/or assisted by the pressure drop. This offers the advantage of allowing a particularly simple control of the holding device, since in particular it is no longer necessary to manually vary the pressure in order to lower the carrier element.

For example, in order to fix the substrate on the support surface, a first negative pressure is initially applied to the cavity of the holding device, and then after the substrate is placed on the carrier element, a second negative pressure is applied to the cavity, for example by covering the suction opening on the support surface with the substrate.

According to one embodiment, the carrier element forces the substrate in the clamped position against the upper side of the body, wherein the amount of force applied to the substrate is such that a possible bending of the substrate is reduced. This offers the advantage that a bent substrate can be smoothed by the holding device. As a result, further processing of the substrate, such as the application of a coating, can be simplified or even permitted. Furthermore, the smoothed substrate can be held in a more stable manner, in particular during rotation of the chuck.

A bent substrate may be a so-called warped wafer. The bending may occur due to a small substrate thickness and/or due to internal stresses in the substrate.

According to one embodiment, the substrate is pulled against the upper side of the body by a negative pressure acting between the substrate and the upper side. This provides the advantage that the substrate in the clamped position can be securely and firmly fixed to the upper side.

According to one embodiment, the method further comprises rotating the substrate, in particular after lowering the carrier element. This offers the advantage that a substrate held particularly stably in this way can be rotated for further processing steps.

100: Holding devices, chucks, movable carrying components

101: Substrate

103: Subject

105: Upper side

107: Carrying components

109: Depression

111: Support surface

113: Cavity

115a: Clamping element, compression spring

115b: Clamping element, compression spring

117a: Spacer

117b: Spacer

119: Sealing means, sealing lip

121: Fluid channel

123a:Fixed means

123b:Fixed means

125: Sealing

201a: Suction opening

201b: Suction opening

201c: Suction opening

201d: Suction opening

203: Fluid channel

205: Application device

300: Manufacturing equipment for microstructure devices

301: Robotic Arm

303: End effector

400: Method for holding substrate

401~407: Method steps for holding substrate

The specific aspects of further examples are explained in detail with reference to the accompanying figures. In the figures: FIG. 1 shows a schematic diagram of a holding device for a substrate; FIG. 2a-d shows a schematic diagram of a holding device during placement of a substrate; FIG. 3 shows a schematic diagram of a manufacturing device for a microstructure device having a holding device; and FIG. 4 shows a flow chart of a method for holding a substrate in a holding device.

FIG. 1 shows a schematic diagram of a holding device 100 for a substrate 101 according to a specific embodiment.

The holding device 100 comprises: a body 103 having an upper side 105; a carrying element 107 arranged in a recess 109 of the body 103 so as to be vertically movable so that it can be adjusted between a protruding loading position and a retracted clamping position, wherein the carrying element 107 comprises a supporting surface 111 for placing the substrate 101, wherein the supporting surface 111 has a smaller diameter than the body 103. Furthermore, the holding device 100 comprises a lifting element which lifts the carrying element 107 to the loading position.

The carrier element 107 seals the recess 109 so that a sealed cavity 113 is provided between the main body 103 and the carrier element 107, which cavity can have the effect of offsetting the lifting element by the negative pressure applied thereto.

The upper side 105 of the main body 103 may correspond to a clamping surface for the substrate 101, on which the substrate 101 is securely clamped in a clamping position.

The carrier element 107 can be received in the recess 109 in a piston-like adjustable manner. By applying negative pressure to the sealing cavity, the carrier element 107 can be moved from the loading position to the clamping position.

The cavity is the space maintained between the bottom of the recess 109 and the carrier element 101. Therefore, the size of the cavity may vary with the position of the carrier element 101 and depend on it.

In an alternative embodiment, the cavity 113 may also be formed by further boring or fluid lines in the body 103.

In the embodiment shown, the lifting element is formed by two clamping elements 115a, 115b in the form of compression springs, which are arranged in the recess 109 of the body 103 and exert a thrust on the carrying element.

In the specific embodiment shown in FIG. 1 , the sealing means 119 is disposed on the surface of the main body. The sealing means 119 can improve the vacuum suction of the substrate 101 in the clamping position on the support surface 111 and/or the surface of the upper side 105 of the main body 103. In particular, the sealing means 119 enables the vacuum to be established on a large surface between the substrate 101 and the holding device 100.

The substrate 101 may be a wafer. The substrate 101 may be disk-shaped. The substrate 101 may have a mostly circular perimeter and a diameter of 2, 3, 4, 5, 6, 8, 12 or 18 inches. Furthermore, the substrate 101 may be mostly flat and may have a thickness between 50 and 4000 microns. The substrate 101 may have straight edges (flat) and/or may have at least one notch. Furthermore, the substrate 101 may have corners, in particular a square or rectangular shape.

The substrate 101 may be formed of a semiconductor material (such as silicon [Si] or gallium arsenide [GaAs]), glass (such as quartz glass), a synthetic material, or a ceramic. The substrate may be formed of a single crystal, a polycrystalline, or an amorphous material. Furthermore, the substrate 101 may include a variety of related materials.

The substrate 101 may include circuits (such as transistors, light-emitting diodes or photodetectors), conductive tracks connecting these circuits, or optical devices and MEMS or MOEMS structures. Furthermore, the substrate 101 may have a coating, such as a structured chromium layer, a pre-crosslinked or hardened bonding adhesive or a separation layer.

Furthermore, the retaining device 100 includes a seal 125 that seals against the side wall of the recess 109 in the body 103. The seal 125 can be an O-ring or a sealing lip.

Furthermore, the carrier element 107 has spacers 117a, 117b on its lower side, for example in the form of bolts.

The spacers 117a, 117b can be used to define the depth of the lowering of the carrying component 107 into the recess 109 and ensure that the supporting surface 111 of the carrying component 107 is arranged to be substantially flush with the upper side 105 of the main body 103 in the clamped position. Furthermore, the spacers 117a, 117b can prevent the carrying component 107 from being completely lowered into the recess, thereby ensuring the minimum size of the cavity 113.

In the specific embodiment shown in FIG. 1 , the carrier element 107 also has fixing means 123a, 123b for fixing the substrate supported on the supporting surface. The fixing means 123a, 123b may be suction openings. Furthermore, the fixing means 123a, 123b may include vacuum boring or vacuum grooves.

The body 103 includes a fluid channel 121 to apply pressure to the cavity 113.

The fluid channel 121 can be a bore in the body 113, in particular a central bore, which leads to the recess 109 or the cavity 113 formed by the recess 109.

According to one embodiment, the holding device 100 has a pressure connector (not shown in FIG. 1 ), by which the pressure in the cavity 113 can be controlled. The fluid channel 121 can connect the cavity 113 fluid to the pressure connector. When negative pressure is applied to the cavity 113, the cavity is also pressed against the fixing means 123a, 123b, whereby the fixing means can apply suction to the substrate 101.

Furthermore, the holding device 100 may include a stopper against which the carrying element 107 is urged into the loading position. Thus, the stopper may be used to define the position of the carrying element 107 in the loading position. The stopper, as it does, may be used to prevent the carrying element 107 from sliding out of the recess 109.

Figures 2a-d show schematic diagrams of a holding device 100 according to a further specific embodiment during placement of a substrate 101.

The carrying element 107 of the holding device 100 of Figures 2a-d includes four suction openings 201a, 201b, 201c, and 201d. The suction openings 201a, 201b, 201c, and 201d form a fixing means to fix the substrate 101 on the supporting surface 111.

The suction openings 201a, 201b, 201c, 201d are fluidically connected to the cavity 113 via the fluid channel 203.

The holding device 100 of Figures 2a-d may include a rotating device (not shown). In particular, the holding device 100 is a rotating chuck, wherein the vacuum is maintained in the hollow shaft of the motor relative to the holding device (also referred to as "chuck") 100 or relative to the cavity 113, so as to apply suction to the substrate 101 on the one hand and adjust the position of the carrier element 107 on the other hand.

FIG. 2a shows the holding device 100 in the loading position before the substrate 101 is placed.

The vertically movable carrier element 107 is raised by a clamping element (also called a "compression spring") 115a~b and urged against a stopper (not shown).

The first negative pressure P1 is applied to the cavity 113, thereby generating a low vacuum in the cavity 113. The resulting force is too small to compress the compression springs 115a~b, so that the carrier element 107 continues to abut against the stopper and protrudes beyond the upper side 105 of the main body 103.

In addition, because the suction openings 201a, 201b, 201c, 201d are fluidly connected to the cavity 113, air can be sucked into the cavity 113, which incidentally can avoid the generation of an excessively strong vacuum in the cavity 113.

FIG. 2b shows the substrate 101 being placed onto the supporting surface 111 of the carrier component 107.

Suction is applied to the substrate 101 through the suction openings 201a, 201b, 201c, 201d on the support surface 111, and the substrate is fixed on the support surface 111. At the same time, the substrate 101 covers the suction openings 201a, 201b, 201c, 201d.

Covering the suction openings 201a, 201b, 201c, 201d prevents air, for example from the surrounding area, from entering the cavity 113. This allows an additional pressure drop to be achieved in the cavity 113, whereby a second negative pressure P2 appears, where P2<P1.

In an alternative embodiment, after the substrate 101 has been placed, the second negative pressure P2 can also be manually adjusted, for example, by a pressure connector on the chuck 100.

Figure 2c shows the carrier component 107 being lowered into the clamping position after being placed on the substrate 101.

The carrier element 107 is lowered due to the pressure drop in the cavity 113. The tension exerted on the carrier element 107 by the negative pressure P2 of the cavity 113 is greater than the thrust exerted on the carrier element 107 by the clamping elements 115a and 115b. As a result, the clamping elements 115a and 115b are compressed.

The degree to which the carrier element 107 is lowered into the recess 109 makes the support surface 111 configured to be approximately flush with the upper side 105 of the main body 103, and the substrate 101 lies not only on the support surface 111 but also on the upper side 105. The maximum lowering depth of the carrier element 107 is determined by the spacers 117a and 117b.

The support surface 111 and the upper side 105 form a common clamping surface for the substrate 101 in the clamping position. In the specific embodiment shown in Figures 2a-d, the diameter of the main body 103 corresponds to the diameter of the substrate, so that the substrate is supported on the upper side 105 and the support surface 111 with its entire rear side.

Alternatively, the body 103 may also have a larger diameter than the substrate, or, as shown in FIG. 1 , may have a smaller diameter than the substrate 101. Thus, the holding device 100 may also be used for particularly small or particularly large substrates 101.

FIG. 2 shows the substrate 101 being processed after the carrier element 107 has been lowered.

During processing, the substrate 101 is rotated, for example by a rotating device (not shown), which causes the main body 103 and the carrier element 107 to rotate.

To this end, the main body 103 can be mounted in a rotatable manner in a rigid holding element of the holding device 100. In particular, the holding device 100 is designed as a rotary chuck.

In addition to the suction openings 201a, 201b, 201c, 201d shown in Figures 2a-d, the main body 103 may also have further fixing means to fix or clamp the lowered substrate 101 on the upper side 105. The further fixing means may include further suction openings.

Furthermore, FIG. 2d shows an application device 205, by means of which a fluid can be applied to the rotating substrate. The fluid is, for example, a lacquer (particularly a photoresist), a coating liquid, a cleaning liquid or a solvent.

In an alternative embodiment, the sealing means 119 (e.g., sealing lips) shown in FIG. 2a-d can be omitted. In the clamped position, the substrate 101 directly contacts the upper side 105 of the main body 103. This provides the advantage of reducing maintenance expenses, because the sealing lips no longer have to be replaced regularly and the sealing lips no longer have to be cleaned. Furthermore, possible floating of the substrate 101 when it is stored on the sealing lips is avoided.

Furthermore, the holding device (or "removable carrying element") 100 can replace the lifting pins for transferring the substrate 101 to the end effector, as is used in known chucks. To deposit the substrate on the holding device 100 or to pick it up from the holding device 100 later, the carrying element 107 can raise the substrate, which means that no additional lifting pins are required.

In an alternative embodiment, the body 103 comprises a further application opening and/or nozzle for the fluid, which is arranged, for example, on the upper side 105 of the body.

If, as shown in FIG. 2 b , the holding device 100 is in the loading position and the substrate 101 is supported on the carrier element 107 , the fluid can be applied to the rear side of the substrate 101 via these further application openings on the upper side 105 .

The fluid can be applied to the surface on the back side of the substrate 101 that is not covered by the carrier element 107. This provides the advantage that the back side of the substrate allows coating, cleaning or solvent treatment without having to lift the substrate 101 from the holding device 100 and turn it over.

FIG. 3 shows a manufacturing apparatus 300 for a microstructure device, which includes a holding device 100 according to a specific embodiment.

The manufacturing equipment 300 may be a coater, a paint coater, a developer, a spin dryer, a mask calibrator, a projection scanner, a laser stepper, a wafer bonder, a mask system, a cleaning system or an imprint system.

The holding device 100 may correspond to the holding device 100 shown in FIG. 1 and/or FIG. 2a-d. The holding device 100 may be connected to a pressure supply of the manufacturing equipment 300.

Furthermore, FIG. 3 shows a robot arm 301, which includes an end effector 303, on which the substrate 101 is supported. By means of this robot arm 301, the substrate 101 can be placed on the holding device 100, wherein the carrying element is raised during the placement of the substrate 101.

FIG. 4 shows a flow chart of a method 400 for holding a substrate 101 in a holding device 100 according to a specific embodiment.

The substrate 101 may be a glass or semiconductor substrate. Furthermore, the substrate 101 may be a wafer or a mask. The substrate 101 may correspond to the substrate 101 shown in FIG. 1 , FIG. 2a-d and/or FIG. 3 .

The method 400 may be performed using the holding device 100 of FIG. 1 and/or FIG. 2a-d and comprises: raising 401 the carrier component 107 to a loading position, wherein the carrier component 107 has a diameter smaller than the substrate 100; placing 403 the substrate 101 on the supporting surface 111 of the carrier component 107; fixing 405 the substrate 101 on the supporting surface 111; and lowering 407 the carrier component 107 to a clamping position.

In the clamped position, the support surface 111 of the carrying element 107 is configured to be approximately flush with the upper side 105 of the main body 103.

The substrate 101 may have a bend or deformation or may be extremely flexible. The curved substrate 101 may be a so-called curved wafer.

The smaller diameter of the carrier element 107 compared to the substrate 101 ensures that suction can be applied even more easily to particularly curved substrates 101 than with a large-surface chuck, since the size of the vacuum surface underneath the substrate 101 is smaller.

According to one embodiment, in order to fix 405 the substrate 101 on the supporting surface 111, a first negative pressure is applied to the cavity 113 of the holding device 100; and in order to lower the carrier component 107 to the clamping position, a second negative pressure is applied to the cavity 113, wherein the second negative pressure is a pressure lower than the first negative pressure.

Applying a negative pressure to the cavity 113 generates a tensile force which counteracts the thrust of the lifting element. During the application of the second negative pressure, the lifting element is adjusted in such a way that the tensile force applied to the carrying element 107 exceeds the thrust of the lifting element. As a result, the carrying element 107 is lowered.

Negative pressure can be applied to the pressure connector of the holding device via an external pressure supply.

In an alternative embodiment, in order to fix 405 the substrate on the supporting surface 111, a first negative pressure is applied to the cavity 113 of the holding device 100; and after the substrate 101 is placed on the carrier component 107, a second negative pressure is applied to the cavity 113, for example, by covering the suction openings 201a~d on the supporting surface 111 with the substrate 101.

In the clamped position, the substrate 101 can be additionally pulled and/or fixed against the upper side 105 of the body 103 by a negative pressure acting between the substrate 101 and the upper side 105.

According to a specific embodiment, the carrier element 107 can cause the bent or deformed substrate 101 in the clamped position to abut against the upper side 105 of the main body 103, so that the force applied to the substrate 101 is large enough to reduce the bending or deformation of the substrate 101.

The substrate can be smoothed and/or clamped by the forces applied in this way.

Furthermore, the method 400 may include rotating the substrate 101, in particular after lowering 407 the carrier component 107 to the clamped position.

After lowering the substrate 101, the substrate 101 can be processed or treated, for example, a coating can be applied to the rotating substrate.

For example, depending on the preset process parameters, the lowering 407 of the substrate 101 can be performed at a predetermined time after the placement 403 of the substrate 101 or immediately after the placement of the substrate 101.

In the manufacturing equipment 300, the operation mode of the holding device 100 is controlled, for example, by a process module.

When the curved wafer is transferred from the substrate holder (robot, spindle with end effector, etc.) to the holding device 100, the process module sends a signal to the substrate holder, for example, that the substrate is received on the already lifted "Z chuck" (carrier element 107), and thus turns off the holding vacuum on the substrate holder. Therefore, the transfer error from the substrate holder to the holding device 100 can be minimized.

As the carrier element 107 with the bent substrate 101 is being lowered, the substrate is centered and guided. No lateral sliding or floating is possible anymore. Sealing means (also called "sealing lips") 119 on the outer area of the holding device 100 (e.g. the upper side 105 of the body 103) can contact the substrate 101 during the lowering process, so that a large surface vacuum is established under the substrate and the substrate 101 is pulled two-dimensionally in a planar manner.

100‧‧‧Holding device

101‧‧‧Substrate

103‧‧‧Subject

105‧‧‧upper side

107‧‧‧Carrying components

109‧‧‧Depression

111‧‧‧Support surface

113‧‧‧Cavity

115a‧‧‧Clamping element

115b‧‧‧Clamping element

117a‧‧‧Spacer

117b‧‧‧Spacer

119‧‧‧Sealing means

121‧‧‧Fluid channel

123a‧‧‧Fixed means

123b‧‧‧Fixed means

125‧‧‧Sealing

Claims (13)

A holding device (100) for a substrate (101), comprising: a body (103) comprising an upper side (105), a carrying element (107), wherein the carrying element (107) is arranged in a recess (109) of the body (103) so as to be vertically movable so that it can be adjusted between a protruding loading position and a retracted clamping position, and wherein the carrying element (107) comprises a supporting surface (111) for placing the substrate (101), wherein the supporting surface (111) has a smaller diameter than the body (103), and a lifting element, which lifts the carrying element (107) to the loading position, And it is constructed to lift the carrying element (107) together with the entire substrate (101) to the loading position, wherein the carrying element (107) seals the recess (109) so that a sealed cavity (113) is provided between the main body (103) and the carrying element (107), the cavity can have a negative pressure applied thereto to offset the effect of the lifting element, and there are spacers (117a, 117b) therein, which define the clamping position of the carrying element (107), where the supporting surface (111) of the carrying element (107) is configured to be substantially flush with the upper side (105) of the main body (103). The holding device (100) of claim 1, wherein the main body (103) has a sealing means (119) which surrounds the carrying element (107) and has a separate interval, and can be sealed between the upper side (105) of the main body (103) and the substrate (101). A holding device (100) as claimed in claim 1, wherein the carrying element (107) is provided with a seal (125) which is sealed against the side wall of the recess (109) in the main body (103). The holding device (100) of claim 1, wherein the carrying element (107) includes fixing means (123a, 123b) to fix the substrate (101) supported on the supporting surface (111). A holding device (100) as claimed in claim 4, wherein the cavity (113) and the fixing means (123a, 123b) form a fluid connection. A holding device (100) as claimed in claim 1, wherein the holding device (100) includes a pressure connector, whereby the pressure in the cavity (113) can be controlled. A holding device (100) as claimed in claim 1, wherein the lifting element comprises clamping elements (115a, 115b) configured to exert force on the carrying element (107) in order to lift it. A holding device (100) for a substrate (101), comprising: a body (103) comprising an upper side (105), a carrying element (107), wherein the carrying element (107) is arranged in a recess (109) of the body (103) so as to be vertically movable so that it can be adjusted between a protruding loading position and a retracted clamping position, and wherein the carrying element (107) comprises a supporting surface (111) for placing the substrate (101), wherein the supporting surface (111) has a smaller diameter than the body (103), and a lifting element, which raises the carrying element (107) to the loading position. The carrier element (107) is provided with a sealing cavity (113) between the main body (103) and the carrier element (107), the cavity having a negative pressure applied thereto to counteract the effect of the lifting element, and wherein spacers (117a, 117b) are provided, which define the clamping position of the carrier element (107), wherein the support surface (111) of the carrier element (107) is arranged to be substantially flush with the upper side (105) of the main body (103), and the spacers (117a, 117b) are arranged on the lower side of the carrier element (107). A manufacturing apparatus (300) for a microstructure device, comprising a holding device (100) as claimed in any one of claims 1 to 8. A method (400) for holding a substrate (101) in a holding device (100), the holding device (100) comprising a main body (103) and a carrier element (107), wherein spacers (117a, 117b) are provided, which define the clamping position of the carrier element (107), wherein the supporting surface (111) of the carrier element (107) is configured to be substantially flush with the upper side (105) of the main body (103), the method comprising the following method steps: raising (401) the carrier element (107) to a loading position, wherein the carrier element (107) has a diameter smaller than that of the substrate (101), placing (403) the substrate (101) on the carrier element (107), The carrier element (107) is mounted on a support surface (111), wherein the carrier element (107) holds the entire substrate (101), fixes (405) the substrate (101) on the support surface (111), and lowers (407) the carrier element (107) to a clamping position, wherein the support surface of the carrier element is configured to be substantially flush with the upper side of the main body, wherein In order to fix (405) the substrate (101) on the supporting surface (111), a first negative pressure is applied to the cavity (113) of the holding device (100); wherein in order to lower (407) the carrier element (107) to the clamping position, a second negative pressure is applied to the cavity (113); wherein the second negative pressure is a pressure lower than the first negative pressure. The method (400) of claim 10, wherein placing (403) the substrate (101) on the support surface (111) of the carrier component (107) generates a pressure drop in the cavity (113) by sealing the suction opening on the support surface (111), wherein lowering (407) the carrier component (107) to the clamped position is triggered and/or assisted by the pressure drop. The method (400) of claim 10 or 11, wherein the carrier element (107) causes the substrate (101) in the clamped position to abut against the upper side (105) of the body (103), wherein the magnitude of the force applied to the substrate (101) is such that possible bending of the substrate (101) is reduced. The method (400) of claim 10, wherein the substrate (101) in the clamped position is pulled against the upper side (105) of the body (103) by a negative pressure acting between the substrate (101) and the upper side (105).